bencodeparser.cpp Example File

torrent/bencodeparser.cpp
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#include "bencodeparser.h" #include <QList> #include <QMetaType> BencodeParser::BencodeParser() { } bool BencodeParser::parse(const QByteArray &content) { if (content.isEmpty()) { errString = QString("No content"); return false; } this->content = content; index = 0; infoStart = 0; infoLength = 0; return getDictionary(&dictionaryValue); } QString BencodeParser::errorString() const { return errString; } QMap<QByteArray, QVariant> BencodeParser::dictionary() const { return dictionaryValue; } QByteArray BencodeParser::infoSection() const { return content.mid(infoStart, infoLength); } bool BencodeParser::getByteString(QByteArray *byteString) { const int contentSize = content.size(); int size = -1; do { char c = content.at(index); if (c < '0' || c > '9') { if (size == -1) return false; if (c != ':') { errString = QString("Unexpected character at pos %1: %2") .arg(index).arg(c); return false; } ++index; break; } if (size == -1) size = 0; size *= 10; size += c - '0'; } while (++index < contentSize); if (byteString) *byteString = content.mid(index, size); index += size; return true; } bool BencodeParser::getInteger(qint64 *integer) { const int contentSize = content.size(); if (content.at(index) != 'i') return false; ++index; qint64 num = -1; bool negative = false; do { char c = content.at(index); if (c < '0' || c > '9') { if (num == -1) { if (c != '-' || negative) return false; negative = true; continue; } else { if (c != 'e') { errString = QString("Unexpected character at pos %1: %2") .arg(index).arg(c); return false; } ++index; break; } } if (num == -1) num = 0; num *= 10; num += c - '0'; } while (++index < contentSize); if (integer) *integer = negative ? -num : num; return true; } bool BencodeParser::getList(QList<QVariant> *list) { const int contentSize = content.size(); if (content.at(index) != 'l') return false; QList<QVariant> tmp; ++index; do { if (content.at(index) == 'e') { ++index; break; } qint64 number; QByteArray byteString; QList<QVariant> tmpList; QMap<QByteArray, QVariant> dictionary; if (getInteger(&number)) tmp << number; else if (getByteString(&byteString)) tmp << byteString; else if (getList(&tmpList)) tmp << tmpList; else if (getDictionary(&dictionary)) tmp << QVariant::fromValue<QMap<QByteArray, QVariant> >(dictionary); else { errString = QString("error at index %1").arg(index); return false; } } while (index < contentSize); if (list) *list = tmp; return true; } bool BencodeParser::getDictionary(QMap<QByteArray, QVariant> *dictionary) { const int contentSize = content.size(); if (content.at(index) != 'd') return false; QMap<QByteArray, QVariant> tmp; ++index; do { if (content.at(index) == 'e') { ++index; break; } QByteArray key; if (!getByteString(&key)) break; if (key == "info") infoStart = index; qint64 number; QByteArray byteString; QList<QVariant> tmpList; QMap<QByteArray, QVariant> dictionary; if (getInteger(&number)) tmp.insert(key, number); else if (getByteString(&byteString)) tmp.insert(key, byteString); else if (getList(&tmpList)) tmp.insert(key, tmpList); else if (getDictionary(&dictionary)) tmp.insert(key, QVariant::fromValue<QMap<QByteArray, QVariant> >(dictionary)); else { errString = QString("error at index %1").arg(index); return false; } if (key == "info") infoLength = index - infoStart; } while (index < contentSize); if (dictionary) *dictionary = tmp; return true; }